1 files changed, 99 insertions, 0 deletions
diff --git a/src/effects/rainbow.c b/src/effects/rainbow.c
new file mode 100644
index 0000000..06b671c
--- /dev/null
+++ b/src/effects/rainbow.c
@@ -0,0 +1,99 @@
+#include <string.h>
+#include <math.h>
+#include <stdio.h>
+#include <assert.h>
+#include <stdlib.h>
+
+#include "scheme.h"
+
+#include "../any_log.h"
+
+typedef struct {
+    effect_t effect;
+    unsigned int speed;
+    cairo_pattern_t *gradient;
+} effect_rainbow_t;
+
+extern double cubic_bezier(double x, double a, double b, double c, double d);
+
+static void effect_rainbow_pre(effect_t *effect, layout_t *layout, cairo_t *cr)
+{
+    struct timespec now;
+    timespec_get(&now, TIME_UTC);
+
+    struct timespec diff = timespec_diff(now, effect->start);
+    double t = (double)timespec_to_ms(diff) / timespec_to_ms(effect->info->duration);
+    double s = cubic_bezier(t, 0.19, 1.0, 0.22, 1.0);
+    (void ) s;;
+
+    effect_rainbow_t *rainbow = (effect_rainbow_t *)effect;
+    double degree = M_PI / 180.0;
+    int radius = layout->height / 2 - layout->y_padding;
+
+    cairo_matrix_t matrix;
+    cairo_matrix_init_translate(&matrix, s, 0);
+    //cairo_matrix_scale(&matrix, layout->x, layout->y);
+    cairo_pattern_set_matrix(rainbow->gradient, &matrix);
+    cairo_set_source(cr, rainbow->gradient);
+
+    cairo_new_sub_path(cr);
+    cairo_arc(cr, layout->x + layout->x_padding + radius, layout->y + layout->y_padding + radius, radius, 90 * degree, 270 * degree);
+    cairo_arc(cr, layout->x + layout->width - layout->x_padding - radius, layout->y + layout->y_padding + radius, radius, 270 * degree, 450 * degree);
+    cairo_close_path(cr);
+    cairo_fill(cr);
+}
+
+static effect_t *effect_rainbow_allocate(const effect_info_t *info)
+{
+    effect_rainbow_t *effect = malloc(sizeof(effect_rainbow_t));
+    effect_init((effect_t *)effect, info);
+
+    effect->speed = 1;
+    effect->gradient = cairo_pattern_create_linear(0, 0, 1, 0);
+    cairo_pattern_set_extend(effect->gradient, CAIRO_EXTEND_REPEAT);
+
+    unsigned int colors[] = {
+        0xff0000, 0xff7300, 0xfffb00,
+        0x48ff00, 0x00ffd5, 0x002bff,
+        0x7a00ff, 0xff00c8, 0xff0000,
+    };
+
+    for (int i = 0; i < 9; i++) {
+        color_t color = color_hex(colors[i]);
+        cairo_pattern_add_color_stop_rgb(effect->gradient, i * (1.0 / 9.0),
+                                         color.r, color.g, color.b);
+    }
+
+    return (effect_t *)effect;
+}
+
+static void effect_rainbow_finalize(effect_rainbow_t *effect)
+{
+    cairo_pattern_destroy(effect->gradient);
+    free(effect);
+}
+
+static bool effect_rainbow_validate(effect_info_t *info, const effect_scheme_t *scheme)
+{
+    return true;
+}
+
+static const config_entry_t effect_rainbow_entries[] = {
+    { 0 },
+};
+
+const effect_scheme_t effect_rainbow_scheme = {
+    .name = "rainbow",
+    .info = {
+        .duration = {
+            .tv_sec = 0,
+            .tv_nsec = 200000000,
+        },
+        .allocate = effect_rainbow_allocate,
+        .finalize = (effect_finalize_t)effect_rainbow_finalize,
+        .pre = effect_rainbow_pre,
+    },
+    .size = sizeof(unsigned int),
+    .entries = effect_rainbow_entries,
+    .validate = effect_rainbow_validate,
+};